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A ug. -1'8, 1925 1,550,312

G. W. FOUKE RECEDING TIMER CAM Original Filed March 2 1922 [12 E qfoeafnz gnu/r5.

J17 W Y Patented Aug". 18, 1925.

UNITED STATES PATENT orrics.

GEORGE VI. FOUKE, OF SACRAMENTO, CALIFORNIA, ASSIGNOB TO CALKY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION 0 13 ILLINOIS.

RECEDING TIMER CAM.

Application filed March 29, 1922, Serial No. 547,898.

T 0 all whom it may concern:

Be it known that I, Gn'oncn W. FOUKE, a citizen of the United States, residing at the city of Sacramento, county of Sacramento, and State of California, have invented new and useful Improvements in Receding Timer Cams, of which the following is a specification.

This invention relates to an electric ignition system for internal combustion engines, and especially to a cam whereby the circuit making and breaking mechanism is actuated.

Practically all internal combustion engines employing electric ignition require a making and breaking mechanism and a cooperating mechanism to either retard or adance the spark. The circuit making and breaking mechanism is in practically all in stances actuated by a. cam fixed on a rotary shaft positively driven from the engine crank shaft, and as such is the case it can readily be seen that the ignition circuit will be actuated whether the engine rotates ahead or reverse. It however happens that most engines of this character are designed to rotate in one direction only and are for this reason usually detrimentally affected by a reversal, particularly when caused by backfiring, due to an advanced spark. lVhere a hand crank is employed for starting purposes, backfiring, caused by an advanced spark, is often disastrous, both to life and limb and any number of cases could be cited where arms have been broken and serious injuries received. The object of the present invention is to generally overcome the objections and dangers above mentioned; to improve and simplify the circuit making and breaking actuating mechanism, and particularly to provide a receding form of cam vhereby backliring and reversal of the engine may be entirely prevented regardless of whether the spark is advanced or retarded. Further objects will hereinafter appear.

T he invention consists of the parts and the construction, combination and arrangement of parts as hereinafter more fully described, and claimed, having reference to the accompanying drawings, in Which Fig. 1 is a plan view of an electric circuit making and breaking mechanism, showing the application of the invention.

Fig. 2 is a cross section of the rotor and the cam carried thereby.

Renewed June 25, 1925.

Fig. 8 is a perspective view of the rotor showing the cam removed.

Fig. 41- is a perspective view of the cam.

Referring to the drawings in detail, and particularly to Fig. 1, A indicates a casing of suitable shape and construction, and 2 and 3 a pair of contacts supported thereby. The contact 2 is in this instance stationary as shown and insulated from the casing, while the contact 3 is supported by a spring arm 4, also secured to the casing as indicated at 5 and insulated therefrom. Journalled centrally f the casing and disposed directly below the spring arm 4 is a shaft 6, and keyed or otherwise secured thereon, as indicated at 7, is a rotor 8. Formed in the periphery of the rotor is a recess 9, and slidably mounted in said recess is a cam member generally indicated at 10. The bottom of the recess presents a flat sliding surface, as at 11, and the lower face of the cam is similarly flat, as at 12. The inner end of this face is however slightly deflected or curved, as at 13, to form a rocking point, hereinafter to be described, while the forward end of the cam terminates in a hook shaped portion 14;, which normally engages a notch or recess 15 formed in the outer face of the rotor. The cam proper, as indicated at 16, which engages with and actuates the spring arm 4-, projects beyond the periphery of the rotor when the shaft 6 rotates in a normal direction, but if the motor and the shaft 6 driven thereby are accidentally or otherwise reversed, the cam will reoede and the spring arm l will be actuated. This is accomplished, due to the fact that the cam as a whole will recede within the recess 9 and thus avoid engagement with the spring arm 4-, that is such engagement as will lift the arm and close the contacts 2 and 3. The receding movement of the cam is limited by a recess 16 formed in the upper face of the cam, said recess terminating in a pair of opposed shoulders 1'? and 18, which are adapted to engage a pin 19 supported in the opposite side walls of the recess 11.. lhe cam is normally held in its projected position, as shown in 1 and 2, by a spring 20. This spring is secured at its lower end, as at 21, in a slot or recess 22 formed in the face of the rotor at approximately right angles to the sliding surface 11 formed in the recess 9. The upper end of the spring engages the rear end of the cam and exerts a suilicient tension to normally hold it projected; the projected position being limited by engagement of the shoulder 18 with pin 19, the receding movement of the cam being similarly limited by engagement of shoulder 17 with the pin 19.

The normal direction of rotation is that indicated by the arrow in Fig. 1. During such rotation cam 16 will engage the lower tl aee of the s 'iring arm and will thus raise the same a snilicient distance to close a circuit between the contacts 2 and 3. However it the direction oi rotation is reversed accidentally or otherwise, snilicient movement to close contacts E2 and 3 will not be obtained. This is due to the fact that the rear side of the cam indit t at $35 woind then first engage the spin arm and a tilting movement would be rted to the cam about the rear rocl race 13-1, which would hit the hook 'iortioii 1iout of engagement with the notch i ant he dotted line position shown at 26 would then be assumed. Further movement of the rotor would cause the cam to i wardly in the recess 9 against the to ion (it the spring, L0 and it would thus entirely reccdc relation to the outer surf or periph ry of the rotor, thereby prove ring closing of the contacts 2 and 3 one as no in, irk would be formed, continued rotatii'rn of the engine or motor would be prevented. The moment the cam passes engaging poz-iition with r lation to mini pressure on the spring 20 would again project the cam and engagement of the-hook l with the notch 15 would be made, thus retaining the cam in its projected position until engagement with arm 92 will be litter. and if the direction of rotation is reversed, recession oi the cam will place. This action of the cam is eX- ceedingly important; first, it an be seen that it is possible to considerably advance the spark befor. starting without any danger of backtiring or reversing the normal direction of rotation; danger to lite and limb is thus awiided; second, detrimental eiiects, such as bacl ring into the carburetor and otherwise me also avoided; third, a rotor and cam constructed here shown (an be employed in connection with practically any type oi circuit making and breale inn mechanism. and such may be installed or applied to standard DLZMIOS of mechanism of this character.

While certain features the present invention are more or less specifically illustrated, l wish it iu'idcrstood that various changes in form and n'o,-' ortion may be resorted to within the scope of the appended claims, similarly that the materials and finish oil? the several parts employed may be such as the experience and judgment oi the manufacturer may dictate or vz'irious uses may demand.

n fag Having thus described my invention, what I claim and desire to secure by Letters Pat ent is- 1. In a device of the character described, a circuit making and breaking actuating mechanism, comprising a rotor, normally turnable in one direction onl a cam 1nem- .1 7 her carried by the rotor and normally proecting beyond the periphery thereof, means permitting a predetermined sliding morement of the cam with relation to the rotor upon reversal of the rotor to permit recession of the cam, and a spring for automatically projecting the cam a predetermined distance.

2. In a device of the character described a circuit making and breaking actuating mechanism, comprising a rotor normally turnable in one direction only, a recess formed in the face of the rotor, a cam memslidably mounted in said recess, said cam normally projecting beyond the periph of the rotor when in one position and movable within the periphery of the rotor when in another position, and means for normally maintaining the cam in proj ted position, said means also permitting recession of the cam within the periplr cry of the recess during reversal of the rotor.

3. ln a device of the character described a rotor, a recess formed in the outer tare thereof, a cam member slidably mounted in said recess and normally projectuu beyond the periphery of the rotor, a spring ei'igaging one end ot the cam and normally maintaining it projected, a hook like member on the opposite end of the cam, a shoulder on the rotor with which the hook like member engages, a recess terminating in stop shoulders formed on the outer face of the cam member, and a pin carried by the rotor ongageable with said shoulders to limit the sliding movement of the cam.

4-. In a device of the character described a rotor, a recess formed in the outer tare thereof, a cam member slidably mounted in said recess and normally projecting beyond the periphery of the rotor, a spring engaging one end of the cam and normally maintaining it projected, a hook like member on the opposite end of the cam, a shoulder on the rotor with which the hook like 1ne1n bcr engages, a recess terminating in stop shoulders formed on the outer face of the cam member, a pin carried by the rotor cngageable with said shoulders to limit the sliding movement of the cam, and means permitting a slight rocking movement oi? the cam with relation to the recess to disengage the hook portion on the cam with relation to the shoulder in the rotor.

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